POISONOUS AND INJURIOUS PLANTS 45 
DescripT1on.—This perennial herb has thick, fleshy, prostrate to 
erect stems, which may be 3 to 6 feet high in cultivated forms; the 
entire plant is smooth. The large, oblong or elliptical, long-stemmed 
leaves develop near the top of the stem. In cultivated forms they 
may be almost entirely green or variegated, with varying numbers of 
white dots or blotches. The leaves are 3 to 6 inches wide and 8 to 
14 inches long, slightly narrowed at the base with blunt-pointed tips; 
they have a prominent midvein from which 9 to 17 pairs of side veins 
arise. Dumbcane contains a milky sap, which is irritating to the 
skin and highly inflammatory to the tongue. The plants, which 
rarely blossom in the warm climate of the Virgin Islands, produce 
blossoms mostly during the winter months. The small, dull-white 
flowers are borne on an elongated stem called a spike. The fruits 
consist of a cluster of scarlet berries. Dumbcane is commonly grown 
for its foliage, and the plants are normally propagated by cuttings, 
though it can be reproduced by seeds. 
DistrisuTion AND Hapirar.—The cultivated form of this plant is 
found in Virgin Islands gardens or, more frequently, as potted house 
plants. It grows wild in moist, shaded places, often in shallow water. 
Dumbcane will grow in full sun if it has a constant and ample supply 
of moisture, but it does better in partial or full shade. The plant 
has a wide tolerance to soil pH but does not do well on shallow, dry 
soils nor on sites exposed to the wind. 
Toxiciry AND Symproms.—AIthough the poisonous nature of dumb- 
cane is still unknown, its leaves were toxic to chicks in feeding trials. 
Humans are sometimes poisoned by dumbcane, but it is of little danger 
to livestock. Juice from dumbcane is highly irritating to the skin 
(10). If chewed and swallowed, the plant causes temporary swelling 
of the throat and loss of speech, hence the name, dumbeane (457). 
MANAGEMENT AND Controt.—Dumbcane is used throughout the 
Virgin Islands as an ornamental. Livestock will not eat the plant 
ordinarily because of its acrid juice. Since the plants are a potential 
danger to livestock, it is desirable to get rid of those not wanted for 
ornament. Grubbing out the plants is effective provided all the roots 
and stems are removed. New plants start readily from the tops and 
stem sections of old plants left lying in shaded, moist places. 
Euphorbiaceae, or Spurge, Family 
Euphorbia pulcherrima Willd. (fig. 24) 
Poinsettia 
DescripTion.—This well-known, ornamental shrub may attain a 
height of 12 feet. The stems are smooth and green in the younger 
parts. The alternate leaves vary in size, shape, and color. The bright- 
colored floral leaves at the stem tips appear to have a whorled arrange- 
ment, and may vary from white through pink to red. The true 
flowers are small, orange structures borne in terminal, compact clus- 
ters. The 3-celled fruiting pod is shallowly grooved; it is about 14 
inch long and wide and contains 3 oblong, smooth, tan seeds. The 
entire plant contains a milky, acrid sap. The plants blossom from 
November to March. They are usually grown from cuttings, but they 
may be air layered. There are several horticultural varieties of 
poinsettia. 
609308 O—62——4 
